import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Enumeration;

@WebServlet("/show")
public class ShowRequestServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //调用 api, 把得到的结果构造成字符串 返回给客户端
        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append(req.getProtocol());
        stringBuilder.append("<br>");
        stringBuilder.append(req.getMethod());
        stringBuilder.append("<br>");
        stringBuilder.append(req.getRequestURI());
        stringBuilder.append("<br>");
        stringBuilder.append(req.getContextPath());
        stringBuilder.append("<br>");
        stringBuilder.append(req.getQueryString());
        stringBuilder.append("<br>");
        //获取所有header
        Enumeration<String> headerNames = req.getHeaderNames();
        while (headerNames.hasMoreElements()) {
            String key = headerNames.nextElement();
            String value = req.getHeader(key);
            stringBuilder.append(key + " : " + value + "<br>");
        }
        //告诉浏览器数据类型
        resp.setContentType("text/html; charset=utf-8");

        //把上述内容返回给客户端
        resp.getWriter().write(stringBuilder.toString());
    }
}
